This prospective observational study will investigate cardiovascular phenotypes in adults with sepsis and hemodynamic instability. Approximately 400 patients requiring vasopressor support will be enrolled across multiple hospital sites. Within 72 hours of admission, participants will undergo peripheral vascular assessments, echocardiography, and blood sampling for cardiac, endothelial, and inflammatory biomarkers. Patients will be classified according to the presence or absence of peripheral vascular dysfunction and cardiac dysfunction. The primary aim is to examine the association between these cardiovascular phenotypes and one-year mortality. Secondary aims include evaluating biomarker profiles, characterizing myocardial injury, and assessing cardiac function at a 3-month follow-up. The study seeks to improve understanding of sepsis-related cardiovascular dysfunction and support development of more individualized management strategies.